Were there ice ages before the Pleistocene? If so, when?

Ice ages are periods of long-term reduction in Earth's temperature, resulting in the expansion of ice sheets and glaciers. The Pleistocene epoch is well-known for its repeated ice age cycles, but it's important to know if there were any ice ages before this time.

The Earth's history is divided into several geological time divisions, among them: 1. Eons: the largest divisions of time, divided into eras. 2. Eras: divisions of an eon, further divided into periods. 3. Periods: subdivisions of an era, further divided into epochs. 4. Epochs: the smallest divisions of geological time, which include the Pleistocene epoch. The Pleistocene epoch is part of the recent Cenozoic era, which started approximately 66 million years ago (Mya) and is divided into three periods: 1. Paleogene period (66 Mya to 23.03 Mya) 2. Neogene period (23.03 Mya to 2.58 Mya) 3. Quaternary period (2.58 Mya to Present), which includes the Pleistocene epoch (2.58 Mya to 11.7 thousand years ago).

There were indeed ice ages before the Pleistocene epoch. Some of them are mentioned below: 1. Huronian glaciation (about 2.4 billion to 2.1 billion years ago): This is one of the earliest known ice ages and occurred during the Paleoproterozoic era in the Precambrian eon. 2. Cryogenian period (about 720 million to 635 million years ago): This period during the Neoproterozoic era of the Precambrian eon is marked by several severe ice ages, including the Sturtian glaciation and the Marinoan glaciation, which are believed to have resulted in a global "Snowball Earth" scenario. 3. Andean-Saharan glaciation (about 460 million to 420 million years ago): This ice age occurred during the Late Ordovician and Early Silurian period of the Paleozoic era. 4. Carboniferous-Permian glaciation (about 360 million to 260 million years ago): Occurred during the Late Carboniferous period and the Early Permian period of the Paleozoic era. This glaciation is particularly well-known for the formation of extensive ice sheets in the southern continents, including Gondwana. In summary, there were several ice ages before the Pleistocene epoch, with glaciation events spanning billions of years throughout Earth's geological history.